Skip to content

Commit

Permalink
native: parse dll files to resolve extern symbols (#19433)
Browse files Browse the repository at this point in the history 
* add simple parsing of dll files to resolve extern symbols
* use enums instead of string values in offsetof functions to reduce bug risks
* add `-d no_backtrace` to native test options
  • Loading branch information
@Spydr06
Spydr06 committed Sep 25, 2023
1 parent 07bd94f commit 20bce37
Show file tree
Hide file tree
Showing 4 changed files with 326 additions and 91 deletions.
7 changes: 6 additions & 1 deletion vlib/v/gen/native/dos.v
View file
Expand Up @@ -3,6 +3,11 @@
// that can be found in the LICENSE file.
module native

const (
dos_header_size = 0x40
dos_header_lfanew_offset = 0x3c
)

pub fn (mut g Gen) gen_dos_header() {
dos_header := [
int(PeMagic.mz),
Expand Down Expand Up @@ -89,7 +94,7 @@ pub fn (mut g Gen) gen_dos_header() {
g.println('; ' + dos_header_description[i])
}
}
if g.pos() != 0x40 {
if g.pos() != native.dos_header_size {
g.n_error('Invalid dos header size')
}

Expand Down
164 changes: 75 additions & 89 deletions vlib/v/gen/native/pe.v
View file
Expand Up @@ -20,8 +20,11 @@ const (
pe_section_align = 0x1000
pe_file_align = 0x0200

pe_coff_hdr_size = 0x18
pe_opt_hdr_size = 0xf0
pe32_plus_opt_hdr_size = 0x70
pe_header_size = pe_file_align
pe_section_header_size = 0x28
pe_stack_size = 0x200000 // gcc default on windows
pe_heap_size = 0x100000 // gcc default on windows
// tcc defaults
Expand All @@ -32,6 +35,9 @@ const (
pe_major_subsystem_version = 4
pe_minor_subsystem_version = 0

pe_header_machine_offset = 4
pe_number_of_sections_offset = 6

pe_num_data_dirs = 0x10

dos_stub_end = 0x80
Expand Down Expand Up @@ -160,7 +166,7 @@ pub fn (mut g Gen) gen_pe_header() {
0x16: '; mSizeOfOptionalHeader'
0x18: '; mCharacteristics'
}
assert 0x18 == pe_header.len * 2
assert native.pe_coff_hdr_size == pe_header.len * 2
}

g.pe_coff_hdr_pos = g.pos()
Expand Down Expand Up @@ -247,28 +253,19 @@ fn (mut g Gen) get_pe32_plus_optional_header() Pe32PlusOptionalHeader {
}
}

enum Pe32PlusOPtionalHeaderField {
size_of_code = 4
size_of_initialized_data = 8
address_of_entry_point = 16
base_of_code = 20
size_of_image = 56
number_of_rva_and_sizes = 108
}

// implemented because __offsetof() + [packed] structs wasn't consistend across OSs
fn pe32_plus_optional_header_offsetof(field string) i64 {
return match field {
'size_of_code' {
4
}
'size_of_initialized_data' {
8
}
'address_of_entry_point' {
16
}
'base_of_code' {
20
}
'size_of_image' {
56
}
else {
panic('pe32_plus_optional_header_offsetof("${field}") not implemented')
}
}
[inline]
fn pe32_plus_optional_header_offsetof(field Pe32PlusOPtionalHeaderField) i64 {
return i64(field)
}

// for later expandability
Expand Down Expand Up @@ -445,25 +442,17 @@ mut:
characteristics int
}

enum PeSectionHeaderField {
virtual_size = 8
virtual_address = 12
size_of_raw_data = 16
pointer_to_raw_data = 20
}

// implemented because __offsetof() + [packed] structs wasn't consistend across OSs
fn pe_section_header_offsetof(field string) i64 {
return match field {
'virtual_size' {
8
}
'virtual_address' {
12
}
'size_of_raw_data' {
16
}
'pointer_to_raw_data' {
20
}
else {
panic('PeSectionHeader.offsetof("${field}") not implemented')
}
}
[inline]
fn pe_section_header_offsetof(field PeSectionHeaderField) i64 {
return i64(field)
}

struct PeSection {
Expand All @@ -475,7 +464,7 @@ mut:

fn (mut s PeSection) set_pointer_to_raw_data(mut g Gen, pointer int) {
s.header.pointer_to_raw_data = pointer
g.write32_at(s.header_pos + pe_section_header_offsetof('pointer_to_raw_data'), pointer)
g.write32_at(s.header_pos + pe_section_header_offsetof(.pointer_to_raw_data), pointer)
}

fn (mut s PeSection) set_size_of_raw_data(mut g Gen, size int) {
Expand All @@ -484,21 +473,21 @@ fn (mut s PeSection) set_size_of_raw_data(mut g Gen, size int) {
}

s.header.pointer_to_raw_data = size
g.write32_at(s.header_pos + pe_section_header_offsetof('size_of_raw_data'), size)
g.write32_at(s.header_pos + pe_section_header_offsetof(.size_of_raw_data), size)
}

fn (mut s PeSection) set_virtual_address(mut g Gen, addr int) {
aligned := (addr + native.pe_section_align - 1) & ~(native.pe_section_align - 1)

s.header.virtual_address = aligned
g.write32_at(s.header_pos + pe_section_header_offsetof('virtual_address'), aligned)
g.write32_at(s.header_pos + pe_section_header_offsetof(.virtual_address), aligned)
}

fn (mut s PeSection) set_virtual_size(mut g Gen, size int) {
aligned := (size + native.pe_section_align - 1) & ~(native.pe_section_align - 1)

s.header.virtual_size = aligned
g.write32_at(s.header_pos + pe_section_header_offsetof('virtual_size'), aligned)
g.write32_at(s.header_pos + pe_section_header_offsetof(.virtual_size), aligned)
}

fn (mut g Gen) create_pe_section(name string, header PeSectionHeader) PeSection {
Expand Down Expand Up @@ -566,19 +555,15 @@ mut:
import_address_table_rva int
}

enum PeImportDirectoryTableField {
name_rva = 12
import_address_table_rva = 16
}

// implemented because __offsetof() + [packed] structs wasn't consistend across OSs
fn pe_idt_offsetof(field string) i64 {
return match field {
'import_address_table_rva' {
16
}
'name_rva' {
12
}
else {
panic('pe_import_table_offsetof("${field}") not implemented')
}
}
[inline]
fn pe_idt_offsetof(field PeImportDirectoryTableField) i64 {
return i64(field)
}

fn default_pe_idt() PeImportDirectoryTable {
Expand Down Expand Up @@ -623,34 +608,35 @@ fn (mut g Gen) gen_pe_idata() {
idata_pos := g.pos()
idata_section.set_pointer_to_raw_data(mut g, int(idata_pos))

mut imports := [
PeDllImport{
name: 'KERNEL32.DLL'
functions: [
'GetStdHandle',
'ExitProcess',
'WriteFile',
// winapi functions
]
},
PeDllImport{
name: 'USER32.DLL'
},
PeDllImport{
name: 'msvcrt.dll'
functions: [
'malloc',
'free',
'printf',
'puts',
'isdigit',
'isalpha',
'memset',
// etc...
]
},
dll_files := ['KERNEL32.DLL', 'USER32.DLL', 'msvcrt.dll']
mut dlls := dll_files
.map(lookup_system_dll(it) or { g.n_error('${it}: ${err}') })
.map(index_dll(it) or { g.n_error('${it}: ${err}') })

g.extern_symbols << [
'GetStdHandle',
'ExitProcess',
'WriteFile',
]

for symbol in g.extern_symbols {
sym := symbol.trim_left('C.')
mut found := false
for mut dll in dlls {
if sym in dll.exports {
found = true
dll.exports[sym] = true
break
}
}

if !found {
eprintln('could not find symbol `${sym}` in ${dll_files}')
}
}

mut imports := dlls.map(it.to_import())

// import directory table
for mut imp in imports {
// generate idt
Expand All @@ -661,7 +647,7 @@ fn (mut g Gen) gen_pe_idata() {
g.gen_pe_idt(&PeImportDirectoryTable{}, 'null entry') // null entry

for imp in imports {
g.write32_at(imp.idt_pos + pe_idt_offsetof('import_address_table_rva'),
g.write32_at(imp.idt_pos + pe_idt_offsetof(.import_address_table_rva),
int(g.pos() - idata_pos) + idata_section.header.virtual_address + 4)

for func in imp.functions {
Expand All @@ -680,7 +666,7 @@ fn (mut g Gen) gen_pe_idata() {

// dll names
for imp in imports {
g.write32_at(imp.idt_pos + pe_idt_offsetof('name_rva'), int(g.pos() - idata_pos) +
g.write32_at(imp.idt_pos + pe_idt_offsetof(.name_rva), int(g.pos() - idata_pos) +
idata_section.header.virtual_address)
g.write_string(imp.name)
g.println('"${imp.name}"')
Expand Down Expand Up @@ -761,10 +747,10 @@ fn (mut g Gen) patch_section_virtual_addrs() {

match section.name {
'.text' {
g.write32_at(g.pe_opt_hdr_pos + pe32_plus_optional_header_offsetof('base_of_code'),
g.write32_at(g.pe_opt_hdr_pos + pe32_plus_optional_header_offsetof(.base_of_code),
section.header.virtual_address)
g.write32_at(g.pe_opt_hdr_pos +
pe32_plus_optional_header_offsetof('address_of_entry_point'), section.header.virtual_address)
pe32_plus_optional_header_offsetof(.address_of_entry_point), section.header.virtual_address)
}
else {}
}
Expand All @@ -774,9 +760,9 @@ fn (mut g Gen) patch_section_virtual_addrs() {
fn (mut g Gen) patch_pe_code_size() {
code_size := int(g.file_size_pos - g.code_start_pos)

g.write32_at(g.pe_opt_hdr_pos + pe32_plus_optional_header_offsetof('size_of_code'),
g.write32_at(g.pe_opt_hdr_pos + pe32_plus_optional_header_offsetof(.size_of_code),
code_size)
g.write32_at(g.pe_opt_hdr_pos + pe32_plus_optional_header_offsetof('size_of_initialized_data'),
g.write32_at(g.pe_opt_hdr_pos + pe32_plus_optional_header_offsetof(.size_of_initialized_data),
code_size)

text_section_index := g.get_pe_section_index('.text') or {
Expand All @@ -791,7 +777,7 @@ fn (mut g Gen) patch_pe_image_size() {
last_section := g.pe_sections.last()
image_size := (last_section.header.virtual_address + last_section.header.virtual_size +
native.pe_section_align - 1) & ~(native.pe_section_align - 1)
g.write32_at(g.pe_opt_hdr_pos + pe32_plus_optional_header_offsetof('size_of_image'),
g.write32_at(g.pe_opt_hdr_pos + pe32_plus_optional_header_offsetof(.size_of_image),
image_size)
}

Expand Down

0 comments on commit 20bce37

Please sign in to comment.